JBL to Polk - worth the "upgrade"

[jdlivestrong]

Hello again,

I've recently upgraded my TV and receiver and it has me thinking about new speakers. My current set up is:

Fronts: JBL Northridge E90's
Center: JBL Northridge E35
Surr; JBL Northridge E10's
Sub: KLH 150w 10"

I've been considering going with the Polk Monitor series speakers; the folks on this forum seem to have lots of good things to say about them. I think I could probably sell my current speakers and getting into the Polk's for only a couple hundred (if that).

Fronts: Polk Monitor 50's
Center: Polk Monitor CS1 or CS10
Surr: Polk Monitor 30's
Sub: Polk Monitor PSW10

I'm hoping some of you might have experience with the JBL's and could offer some advice on whether or not I would really be upgrading my sound experience (maybe I'd be taking a step back)...or if my money would be better spent somewhere else in my set up.

I would appreciate any and all advice you might have.

**UPDATE: found some Definitive Technology speakers...see post 11**